template.json

{
    "variables": {
        "aws_access_key": "{{ env `AWS_ACCESS_KEY_ID` }}",
        "aws_secret_key": "{{ env `AWS_SECRET_ACCESS_KEY` }}",
        "region": "us-east-2",
        "source_ami": "ami-0e83be366243f524a",
        "instance_type": "t2.small"
    },
    "sensitive-variables": [
        "aws_access_key",
        "aws_secret_key"
    ],
    "builders": [
        {
            "type": "amazon-ebs",
            "access_key": "{{ user `aws_access_key` }}",
            "secret_key": "{{ user `aws_secret_key` }}",
            "region": "{{ user `region` }}",
            "source_ami": "{{ user `source_ami` }}",
            "instance_type": "{{ user `instance_type` }}",
            "ssh_username": "ubuntu",
            "ami_name": "Ubuntu-Docker-{{ timestamp }}"
        }
    ],
    "provisioners": [
        {
            "type": "shell",
            "script": "scripts/install_docker.sh"
        },
        {
            "type": "shell",
            "script": "scripts/create_app_user.sh"
        },
        {
            "type": "shell",
            "script": "scripts/prepare_db_mountpoint.sh"
        }
    ]
}